School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS (UK) http://www.chm.bris.ac.uk/org/bmilburn/index2.htm.
Angew Chem Int Ed Engl. 2015 Jan 26;54(5):1527-31. doi: 10.1002/anie.201410115. Epub 2014 Dec 5.
Fused cyclobutenes, prepared by the photocycloaddition of propargyl alcohols to cyclic anhydride chromophores, undergo facile thermochemical ring opening to fused γ-lactones. The size of the fused ring profoundly influences the temperature that is required to facilitate the ring opening (from 50 °C to 180 °C) and the nature of the product that is formed. Our studies provide new insights into the mechanistic course of these reactions and have been extended to facilitate the preparation of lactams fused to medium-sized rings.
稠环丁烯是通过炔丙醇与环状酸酐发色团的光环加成反应制备的，容易发生热化学反应开环生成稠合γ-内酯。稠合环的大小对促进开环所需的温度（从 50°C 到 180°C）和形成的产物的性质有很大影响。我们的研究为这些反应的机理过程提供了新的见解，并已扩展到促进制备与中环稠合的内酰胺。
